1. Field of Invention
The present invention relates to a multi-layer structure. More particularly, the present invention relates to an enhanced wavelength-converting structure.
2. Description of Related Art
A wavelength-converting structure has been used for converting a first light into a second light. The wavelength-converting structure may include a substrate and a wavelength-converting material. An adhesive can combine the substrate and the wavelength-converting material. The wavelength-inverting structure can be utilized in a light-emitting diode (LED), such as a phosphor based LED. The wavelength-converting structure can merely convert the first light in to the second light. However, a part of the second light would emit to the substrate, but another part of the second light would emit backward to the light source. The part of the second light emitting backward to the light source would be utilized efficiently and be wasted. For the forgoing reasons, the present invention provides an enhanced wavelength converting structure with a wavelength-selective reflecting layer to improve light emitting efficiency.